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#1
A20 / Re: A20 Board Power Consumptio...
Last post by LubOlimex - December 15, 2025, 10:15:09 AMThese are power-hungry processors not designed with low power modes in mind, not a lot of current can be saved especially if you want to use the boards at their full capability. Yet, you can limit the CPU clock, the RAM clock and much more to reduce the power consumption to a minimum. Hard to say what is the minimum since it depends on the goals and what you are willing to sacrifice.
#2
UEXT / Re: MOD-IRDA faulty ?
Last post by LubOlimex - December 15, 2025, 09:31:06 AMIs this about receiving or sending (both have 33R resistor)? I guess it is the sender. Changing R1 down to 20R should be alright. This will bring the current to absolute maximum of 100mA.
The 33R that we use is calculated as follows - supply 3.3V DC, forward voltage of SIR-32ST3F - 1.3V - means voltage is 3.3V - 1.3V = 2.0V
2.0V/33R~0.06A
If you use 20R - 2.0V/20R=0.1A
Refer to the datasheet:
https://fscdn.rohm.com/en/products/databook/datasheet/opto/optical_sensor/infrared_led/sir-34st3f-e.pdf
The 33R that we use is calculated as follows - supply 3.3V DC, forward voltage of SIR-32ST3F - 1.3V - means voltage is 3.3V - 1.3V = 2.0V
2.0V/33R~0.06A
If you use 20R - 2.0V/20R=0.1A
Refer to the datasheet:
https://fscdn.rohm.com/en/products/databook/datasheet/opto/optical_sensor/infrared_led/sir-34st3f-e.pdf
#3
A20 / A20 Board Power Consumption in...
Last post by annasm - December 15, 2025, 06:42:52 AMHi everyone, I'm using an A20 OLinuXino board for a low-power project. I'd like to know the typical power consumption of the board when it's in sleep or idle mode with no peripherals connected. Are there any recommended settings or tweaks to minimize power usage in this state? Thanks in advance!
#4
UEXT / Re: MOD-IRDA faulty ?
Last post by SirExie - December 14, 2025, 02:17:16 PMHi Folks,
Follow up post again, I now have it working, the protocol is correct, its not Whynter at all, its NEC!
But I'm now on to another problem, I cant get the range I want. Ideally, I'm looking for ~3m.
Looking at MOD-IDRA I notice it had a 33 ohm resistor which by rough maths makes it about 50mA (I think). It looks like a surface mount 0805 which I'm a chance at re-working.
So how bad would it be to put a 20R in there ? I should be about to get a .25W or maybe a .333W and this should push the IR diode a bit harder maybe 80-90mA ?
Sorry if its poor form to talk about hacking away at the Olimex product here, I'm not an electrical engineer, if this is a bad idea, just tell me and I'll come up with a different solution.
Follow up post again, I now have it working, the protocol is correct, its not Whynter at all, its NEC!
But I'm now on to another problem, I cant get the range I want. Ideally, I'm looking for ~3m.
Looking at MOD-IDRA I notice it had a 33 ohm resistor which by rough maths makes it about 50mA (I think). It looks like a surface mount 0805 which I'm a chance at re-working.
So how bad would it be to put a 20R in there ? I should be about to get a .25W or maybe a .333W and this should push the IR diode a bit harder maybe 80-90mA ?
Sorry if its poor form to talk about hacking away at the Olimex product here, I'm not an electrical engineer, if this is a bad idea, just tell me and I'll come up with a different solution.
#5
UEXT / Re: MOD-IRDA faulty ?
Last post by SirExie - December 12, 2025, 01:48:27 PMJust a follow up - I ended up getting an old Gopro Session camera and rigging it up to watch the transmit LED, and it DOES show the LED blinking.
It may not be a super scientific test, but I hope it confirms the hardware is ok and as LubOlimex pointed out, it's just the code.
I'm using ESPHome and I might just be struggling to get it to support Arlec signalling, which I'm guessing is Whynter from the earlier test which it determined from the Arduino-IRremote library.
It may not be a super scientific test, but I hope it confirms the hardware is ok and as LubOlimex pointed out, it's just the code.
I'm using ESPHome and I might just be struggling to get it to support Arlec signalling, which I'm guessing is Whynter from the earlier test which it determined from the Arduino-IRremote library.
#6
ARDUINO / Re: BC66 NB-IoT Module (DevKiT...
Last post by LubOlimex - December 11, 2025, 01:13:06 PMMaybe try this, refer to the comments in the README files: https://github.com/OLIMEX/NB-IoT/tree/master/SOFTWARE/AT_restore_tool
#7
ARDUINO / Re: BC66 NB-IoT Module (DevKiT...
Last post by LubOlimex - December 11, 2025, 08:09:56 AMHmm, so even Quectel support doesn't have the AT firmware?
#8
ARDUINO / Re: BC66 NB-IoT Module (DevKiT...
Last post by ameero95 - December 10, 2025, 11:31:09 AMHello LubOlimex,
I guess I am out of luck here huh?
Quote from: LubOlimex on December 03, 2025, 01:16:07 PMDid you write e-mail to the support or post in the forums? Please post in the Quectel forums and link me the forum thread where you requested the firmware.
I guess I am out of luck here huh?
Quote from: Jonathan Wang (Quectel Forum Support) on December 03, 2025, 01:16:07 PMThis module is EOL already. Much appreciation https://forums.quectel.com/t/re-how-to-get-quectel-standard-firmware/53512?u=ameer
#9
New Products release / FOSDEM 2026
Last post by olimex - December 10, 2025, 09:57:34 AMOur Soldering Workshop proposal has been officially accepted for FOSDEM 2026.
On 31 January, from 10:00 to 17:00, participants will assemble the RVPC, an open-source hardware and software retro-style RISC-V computer. https://olimex.wordpress.com/2025/12/10/we-will-run-soldering-workshop-for-rvpc-the-retro-style-risc-v-computer-on-fosdem-2026/ #fosdem #riscv #oshw #floss
On 31 January, from 10:00 to 17:00, participants will assemble the RVPC, an open-source hardware and software retro-style RISC-V computer. https://olimex.wordpress.com/2025/12/10/we-will-run-soldering-workshop-for-rvpc-the-retro-style-risc-v-computer-on-fosdem-2026/ #fosdem #riscv #oshw #floss
#10
UEXT / Re: MOD-IRDA faulty ?
Last post by LubOlimex - December 09, 2025, 09:13:22 AMUmm easiest way is with another MOD-IRDA, but also with some device (TV, AIRCON, etc) that you know for sure what protocol it uses, and then use the same protocol on the PoE + MOD-IRDA combo.